Please tell me how to fix this rigging problem
This model is very complex and requires manual weights editing. The automatic weights or Mixamo could only be a starting point.



The model is ripped with losses. There is no material data, and it's probably missing a small part and a vertex color data. This kind of game model demands deep 3D knowledge.



I made a rigging with Mixamo and tried to set up materials. I have not figured out how exactly those alpha maps are used, but overall it is correct. The weights still need attention.





A small tip I have learned: by default, Blender ignores color data for pixels with zero alpha, and you need to set Alpha from Straight to Channel Packed so it will not affect RGB value.